Coupling for pipes, piles, and like elements



Jan. 17, 1950 R. MULDER 2,494,826

COUPLING FOR PIPES, FILES, AND LIKE ELEMENTS Filed Dec. 4, 1945 FIG. 5

RUDOLF MULDER',

ATTORNEY Patented Jan. 17, 1950 UNITED ELEMENTS Rudolf Mulder, Haarlem,Netherlands Application December 4, 1945, Serial No. 632,635

In Germany August 5, 1944 2Claims. (Cl. 287----54) In the building ofscaffolds and like constructions it is important that the coupling forpipes, piles or like elements to be interconnected and of which thescaffold is to be built up, consists of as few simple partsaspossible,and that no use is made of parts such as wedges and like elements thatare liable to get lost. Theinvention relates to a coupling hicomplieswith these requirements.

According H coupling is characterized by at least two straps detachablyor rigidly interconnected, or being integral, and thetwo ends of whichprojecting beyond the pipe or the like to be embraced, are

each provided with an opening, a clamping block being rotatable in eachpair of openings, the clamping surface of said block being eccentricwith respect to the axis of rotation in such a manner that the clampingforce increases if the load increases. Preferably according to theinvention each clamping piece is revolvable due to its axialdisplacement by reason of the fact that at its one end it is providedwith a helical or like sliding surface which by sliding over an edge ofthe opening, that in the direction of axial displacement is the mostremote, is revolved in the sense of clamping the clamping piece in aselflocking Way.

Further according to the invention the corresponding edges of the holesof each strap may be located in planes intersecting one another at anacute angle, the one hole being wider than the other and the wider holeserving for the introduction of the clamping block until the helical orlike sliding surface thereof will come to bear 1 upon the sliding edgeof the other opening, both holes having a circular bent wall portion onwhich a corresponding part of the clamping piece is turning when thelatter is revolved.

This construction is very simple on account of its small number ofparts; locking keys are no more necessary. Further the manipulation iseasy and the clamping action faultless and selflocking.

Preferably each clamping piece is connected to the corresponding strapin such a manner that it may be removed from the pair of openingsconcerned. In this case the coupling does not have any loose parts.

The drawing illustrates the invention by an embodiment.

Fig. 1 shows a front elevation of a coupling according to the inventionwhen applied to two pipes.

Fig. 2 is a rear view of the left coupling strap of Fig. 1.

Fig. 3 is a front elevation of a clamping block and.

Fig. 4 is a sideor end elevation thereof.

In Fig. 1 the pipes to be coupled are denoted to the mvnu jn to this endthe by I and 2; they cross each other perpendicularly. The couplingcomprises two U-shaped istraps 3 and 4 the webs of which areinterengaging; the webs constitute the strap parts embracing the tubesdirectly. In the straps arms 5 and B of the right strap 3 which armslaterally project from said webs,and also in the strap arms of the leftstrap 4, the arm I only of which is visible in the front elevation,holes are provided which for each pair of arms of a strap are locatedopposite one another. These pairs of holes serve each to: receiveaclamping block 8 or 9 respectively that is rotatable and axiallyslidable therein. 'Each clamping block consists of a rod havingthe'desired section and having a particular shape at the one end. InFig. 1, on

the left, the hole in the strap arm 'I is indicated by IIl the loweredge I I of thehole in the drawing makes an acute angle with the loweredge I2 of the hole 2I in the rearmost strap arm 22 non-visible in Fig.1 but shown in Fig. 2. The two lower edges II and I2 are thus located inplanes intersecting one another at an acute angle and beingperpendicular to the plane of the drawing.

The front hole I0 is wider than the rear hole 2|. Each rod shapedclamping block. (Figs. 3 and 4) at one end is provided with a helicallyshaped sliding surface I3 that at the one extremity of the clampingblock is bounded by the tangent, passing from the centre of theeccentric edge of that extremity I4 up to the circle of rotation I!(contact point 24) and by two lines, one of which begins at I4 andextends over the clamping surface of the clamping block and the other ofwhich begins at 24 and extends over the flat side of the clamping block,which two lines meet each other at I6. The sliding surface I3 is adaptedto co-operate with the lower edge I2 of the-in Fig. 1rear hole 2i insuch a manner that when the clamping block is axially displaced from thefront to the rear, the lower edge I2 on account of its contact with thehelical surface 13, sliding thereon, produces a rotation of the clampingblock in the direction of the arrow (Figs. 1 and 2) resulting in aself-locking clamping of the eccentric clamping surface I5 against thepipe 2.

The clamping block is passed through the wide front hole I0 until thehelical surface I3 will come to rest with its end upon the lower edge I2of the rear hole 2I. This hole just as the front hole III is providedwith a circularly bent wall portion 23 on which the corresponding partof the clamping block will rotate; further the holes l0, 2| have such ashape that rotation of the clamping block on account of the cooperationof the helical sliding surface I3 with the lower edge l2 of the rearmosthole 2I is not interfered with, as will appear from the drawing. Whenthe clamping block has been placed in the above mentioned .position:with the-helical surface 13 on the. lower. edgexl'2.v of thearearmosthole 2!, then during further driving in, e. g. by some hammer strokes,an automatic revolving of the."

clamping block is produced in the manner described above.

In the embodiment described above and illustrated in the drawing variousstructural modifications may be made within the spirit of the invention.

For instance the coupling instead of having one pipe supporting surfacemay have? two. supporting surfaces located in the longitudinal axis ofthe. pipe.

Furthergthe coupling. according to the inventionbesides for.pipes,..piles arrdthelike may be used;advantageouslyfor...interconnecting other suitably. shapedbodiesorobiects.

.Jlclair'n:v .1. A. pipe supportbomprising, a plurality of .U -.shaped'straps. interengaged; at the closed ends thereof, each free-send-ofjeachsaid strap having v a n opening.thereinandfdrming pairs of open--ingsin. each=of said u-shaped straps, a clamping member. extending.throu ghqeach. said. pair of openings. for clamping} a.; pipe.therebetween and .saidQU-s'haped strapa said znember comprising abarhaving aneccentrieblamping surface there- .0.n,,- and a.-liel-ical"shaped sliding surface on an -.nd. thereof wherebyupon. entry of onesaid member-ins one-said pair}- oilopenings said member will be tiltedby coaction of said helical sliding surfaceswith anl-edge oiaoneoi.saidopenings and provide. a self-locking: clamping. ofv said. pipe.

2. A pipe support as claimed in claim 1, an

edge of one of said openings in each said pair being in aplanedifierentfrom that of an edge .in-a c'oacting'one of said pair of openings, the

said planes of said edges intersecting at an acute angleaonepf saidopenings in a pair being larger than the other said opening and servingfor the introduption of said clamping member to the 'edge'of the othersaid opening in a plane different .from-rthat of said larger opening,and said openings having curved. wall portions, whereby saidclamping,memberflisrmtated in.said.,curved..wall

portions fdhringit'ilting thereojgbyflsaid helical RU JQIFMULDER. "RFERE C S- I D :followingi references are: of: -reeord;;in thefileiofithisg mtentt UNITED s'rAirEs ATEN- rs

